To integrate your MailerLite account with Optingun, go to your top right dropdown menu and choose integrations. Choose Optingun and copy your account API key.
Next, Log in to your Optingun account. Go to the hamburger menu in the top left and choose API configuration. Choose MailerLite and paste in your API key. Hit Save.
Now all of your settings are automatically saved. To connect your form to MailerLite, go and make a new form, then from "Settings", "Integrations" choose "MailerLite". Choose your group and click "Add this Integration". Thats it now your forms are connected!